Struct Factor 

pub struct Factor {
    pub variables: Vec<String>,
    pub values: ArrayD<f64>,
    pub name: String,
}

A factor in a probabilistic graphical model.

Represents a function over a subset of variables: φ(X₁, X₂, …, Xₖ) → ℝ⁺

Fields

variables: Vec<String>

Variables this factor depends on

values: ArrayD<f64>

Probability/potential values

name: String

Factor name for debugging

Implementations

impl Factor

pub fn new( name: String, variables: Vec<String>, values: ArrayD<f64>, ) -> Result<Self>

Create a new factor.

pub fn uniform(name: String, variables: Vec<String>, card: usize) -> Self

Create a uniform factor.

pub fn normalize(&mut self)

Normalize factor to sum to 1.

pub fn get_cardinality(&self, var: &str) -> Option<usize>

Get cardinality of a variable.

impl Factor

pub fn product(&self, other: &Factor) -> Result<Factor>

Compute the product of two factors.

φ₁(X₁) * φ₂(X₂) = φ(X₁ ∪ X₂)

pub fn marginalize_out(&self, var: &str) -> Result<Factor>

Marginalize out a variable by summing over it.

∑ₓ φ(X, Y) = φ(Y)

pub fn marginalize_out_vars(&self, vars: &[String]) -> Result<Factor>

Marginalize out multiple variables.

pub fn marginalize_out_all_except(&self, keep_vars: &[String]) -> Result<Factor>

Marginalize out all variables except the specified ones.

This is useful for extracting marginals: to get P(X), marginalize out all variables except X.

pub fn maximize_out(&self, var: &str) -> Result<Factor>

Maximize out a variable (for max-product algorithm).

max_x φ(X, Y) = φ(Y) where φ(Y) = max over X

pub fn maximize_out_vars(&self, vars: &[String]) -> Result<Factor>

Maximize out multiple variables.

pub fn divide(&self, other: &Factor) -> Result<Factor>

Divide this factor by another factor.

φ₁(X) / φ₂(X) - used for message division

pub fn reduce(&self, var: &str, value: usize) -> Result<Factor>

Reduce factor to specific variable assignment (evidence).

Trait Implementations

impl Clone for Factor

fn clone(&self) -> Factor

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Factor

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Factor

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for Factor

fn eq(&self, other: &Factor) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl QuantRSDistribution for Factor

fn to_quantrs_distribution(&self) -> Result<DistributionExport>

Convert a factor to a QuantRS-compatible distribution.

fn from_quantrs_distribution(dist: &DistributionExport) -> Result<Self>

Create a factor from a QuantRS distribution.

fn is_normalized(&self) -> bool

Check if the distribution is normalized.

fn support(&self) -> Vec<Vec<usize>>

Get the support (valid values) of the distribution.

impl Serialize for Factor

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Factor